While other big U.S. chicken companies race to cut antibiotics use from their production, Joe Sanderson, who runs one of the largest, says he isn’t budging.

The chief executive of Sanderson Farms Inc. said the company will continue to encourage its chicken farmers to administer the drugs to prevent illness and to treat sick birds. He called public-health concerns over antibiotic-resistant bacteria overblown and argued that the meat industry’s decadeslong use of such drugs has yet to prove a problem.